Field of the Invention
The present invention particularly relates to a three-dimensional measurement apparatus, a three-dimensional measurement method and a program for measuring a three-dimensional shape of an object having a minute shape.
Description of the Related Art
In the past, a light section method has been known as a three-dimensional-shape measurement method supporting a dynamic scene. The light section method projects an illumination pattern containing a plurality of parallel lines to an object (hereinafter, such a plurality of parallel lines will be collectively called a multi-slit, and each of the lines will be called a measurement line). The light section method using a plurality of measurement lines may be implemented through identification of the ordinal number in a projected multi-slit of a measurement line observed on an object. One method for identifying a measurement line number indicating the ordinal number of a measurement line in a multi-slit may use a pattern including some feature (identification feature) added to a multi-slit.
Japanese Patent Laid-Open No. 1-274007 discloses a method which measures a three-dimensional shape by using a pattern including slits randomly arranged on measurement lines of a multi-slit. According to the method, a measurement line is divided into a plurality of segments so that the measurement line is identified through calculation based on positions of two points of both ends of the segments.
As described above, measurement of a three-dimensional shape of an object may require identification of a measurement line number of an observed measurement line of a multi-slit. Because the method disclosed in Japanese Patent Laid-Open No. 1-274007 may require a length for two points of both ends of a segment for identification of a measurement line number, a measurement line number may not be identified in a minute part. As a result, a three-dimensional shape of an object having a minute shape may not be measured.
The present invention provides a technology which allows robust measurement of a three-dimensional shape of an object having a minute shape.